The present invention relates to an indirect hot water cooling device for a steam humidifier.
When steam generating humidifiers need to be drained down for maintenance or for periodic removal of accumulated minerals, it is necessary to cool this boiling water below 140° F. Since waiting for the tank to cool down via the ambient air is such a slow an inconvenient method, some steam generating humidifiers use a device that mixes cooler municipal water with the hot water to achieve the desired mixed water temperature so that the effluent water is not too hot.
Recently, due to the lack of potable water in California, a restriction has been placed on the use of municipal water supplies to mix with and cool boiling/hot water. This restriction prevents the use of current designs which simply mix enough cool water to bring the temperature down to an acceptable temperature.
Accordingly, there is a need to provide a mechanism to chill or reduce the temperature of the water in the humidifier tank prior to discharging the water from the tank without mixing cooler municipal water with the hot water.
U.S. Pat. No. 6,792,963 discloses a hot water humidifier with an automatic siphon drain fed with cooler source water that is flushed via a drain. The hot water humidifier includes a humidifier tank supplied with the cooler source water. The automatic siphon is an inverted substantially U-shaped siphon conduit automatically operable with respect to the humidifier tank having one end coupled to the tank and the other end coupled to the drain. The humidifier also includes a source conduit coupled to and feeding the cooler source water to the humidifier tank. A valve controlling the cooler source water feeds the source water into the humidifier tank to maintain the temperature of an admixture of cooler source water and any preexisting tank water at or below a predetermined temperature during a flush cycle. The tank is flushed and drained via the automatic siphon based upon the level of the admixture in the tank and the level of admixture in the siphon. The source conduit which feeds water to the tank may be coupled to the humidifier tank via the siphon conduit.
U.S. Pat. No. 6,658,876 discloses a method and apparatus for collecting and chilling wastewater samples and the like and provides an insulated sample container vessel that has cooling coils therein for direct contact and heat transfer with a liquid in the container to rapidly cool the liquid. A refrigeration unit keeps the cooling coils cool. The liquid can be a sample which is required to be stored at 1-3 degrees Centigrade. The chiller is different from similar chillers in that the cooling coils simply are inserted in an insulated container, and can be removed therefrom when it is desired to transport the sample. The sample remains cool during transportation even without the cooling coils. The cooling coils are arranged in the ice chest such that coolant from the chiller enters through the upper coils and exits through the lower coils, causing the liquid sample in the upper part of the container to cool more than the sample in the lower part of the container. The liquid sample drifts down to the bottom, and the warmer sample in the container drifts upwardly, so there is no need for a mechanical stirrer to circulate the sample to make it uniformly cool. The container has a fitting that enables a selected sample to be added to the container interior while the container remains closed.
U.S. Pat. No. 7,578,967 discloses an apparatus and a system that reduces water wasting, when compared to contemporary sterilizer systems. The apparatus eliminates the need for needle or other valves in sterilizers or sterilizer systems and, thus reduces the cool water from running constantly, so as to conserve water. The apparatus can be combined with conventional sterilizers and/or sterilizer systems to collapse steam from these sterilizers and/or sterilizer systems and provide it to a drain line or drain at a temperature sufficiently cool in accordance with building codes (typically less than 140 degrees F.).
None of these patents discloses an indirect hot water cooling device for a steam humidifier that uses a closed-loop chilled water supply as a source of a heat sink to a cooling tank separate from the steam humidifier tank. For example, U.S. Pat. No. 6,792,963 pipes cool water directly into the humidifier tank. Also, this patent does not disclose a closed-loop chilled water supply, so that the cool water is not recycled.
None of these patents discloses an indirect hot water cooling device for a steam humidifier that uses a heat exchanger to supply chilled water to a cooling tank separate from the steam humidifier tank.
None of these patents discloses an indirect hot water cooling device for a steam humidifier that uses a separate, cleanable cooling tank to receive hot water drained from the steam humidifier.
Other advantages and features of the present invention will be further described below.